The effect of formation of the liquid crystalline phase on the blood compatibility of a cholesterol modified silicone.

Cholesterol modified silicones were synthesized by grafting copolymerization of 10-Cholesteryloxydecanol onto polymethylhydrosiloxane (PMHS). Fourier transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance ((1)H-NMR) spectroscopy and gel permeation chromatography (GPC) confirmed the chemical structures of polymers. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) results indicated the mesogenic properties of those polymers. The modified silicone with 45% 10-Cholesteryloxydecanyl (SC45) indicated obvious thermotropic liquid crystalline transform at about 122-124.9 degrees C. The thermotropic liquid crystalline phase could be retained at room temperature via a special annealing/quenching process. The anneal-quenched film (SC45C) formed continuous liquid crystalline phase, whereas the unannealed films presented amorphous structure. The blood compatibility of the coatings was assessed from SEM observation of the platelet's adhesion to coating surface and plasma recalcification time (PRT). The results revealed that the formation of the liquid crystalline phase could greatly improve the in vitro blood compatibility of the materials. The positive results of liquid crystalline onto haemocompatibility allow broad potential in biomaterials.